1. Field of the Invention
The invention relates to a vehicle seat that includes a frame member and a support member (i.e., a member that supports an occupant) that is attached to the frame member.
2. Description of the Related Art
Japanese Patent No. 4228355 describes one such vehicle seat. This vehicle seat includes a seat cushion and a seat back that is connected in an upright position to the seat cushion. The seat cushion includes a frame member and a support member. The frame member is a generally rectangular frame-shaped member that forms a seat frame and includes an upright piece. This upright piece is a flat plate member that extends in the longitudinal direction of the seat, and is arranged on an upper surface (a surface facing the support member) of the frame member. Also, the support member is a member that supports an occupant, and includes a frame-shaped body and a sheet-shaped body. The frame-shaped body is a frame-shaped member that has a shape that follows the outer shape of the frame member (i.e., the sitting side of the frame member), and includes a hole into which the upright piece is inserted. Also, the sheet-shaped body is a sheet-shaped member that is able to elastically expand and contract, and is stretched across the center of the frame-shaped body. With the technology described in Japanese Patent No. 4228355, the upright piece is inserted into the hole while the frame-shaped body is overlapped with the frame member. Then after the upright piece is made to protrude from the hole, it is bent in the width direction of the seat, thus enabling the support member to be fixed to (so as not to become detached from) the frame member.
Incidentally, with this kind of vehicle seat, considering maintenance and design changes and the like of the seat, it is preferable to be able to detach the support member from the frame member. Therefore, with a seat back described in Japanese Patent No. 4069307, an inner portion of a support member is made hollow and is able to be covered by a frame member. Then a protruding portion (having a flat plate shape) that extends in the vertical direction of the seat is formed on a side surface of the frame member, and a groove portion into which this protruding portion can be inserted is formed in the frame-shaped body. Then the support member is slide downward from above the frame member (that is in an upright position), and covered. Next, the protruding portion is fitted into the groove portion, thereby enabling the support member to be detachably attached to the frame member.
Incidentally, with the technology described in Japanese Patent No. 4069307, the support member is slid downward from above the frame member (that is in an upright position). This presents difficulties, such as the support member hitting another member such as the ceiling or the like, for example, when attaching the frame member while inside the vehicle. Also, with the technology described in Japanese Patent No. 4069307, the support member is retained by the engagement of the protruding portion in the groove portion (i.e., by one type of engaging structure), so the engaging force of the support structure with respect to the frame member is somewhat weak. Therefore, the support member rattles against the frame member when an occupant sits down, for example. That is, the structure provides fairly weak attachment stability. Therefore, the technology described in Japanese Patent No. 4069307 is simply unable to be used with the technology described in Japanese Patent No. 4228355, considering the attachment stability and workability and the like.